code: def test_directed(self):
      plt.close("all")
      g = Graph.Ring(5, directed=True)
      fig, ax = plt.subplots()
      plot(g, target=ax, layout=self.layout_small_ring)
  
imports: import os
  import unittest
  from igraph import Graph, plot, VertexClustering, Layout
  from ...utils import overridden_configuration
label_desc: Use image node_id 6 for calling the GraphTestRunner obj's underlying member method code with example usage: obj.test_directed() without return types